This research program endeavors to bridge the gap between the investigation of human psychological processes and basic neurobiologic studies of brain mechanisms. By recording brain potentials temporally related to specific psychomotor sequences in adults, infants, children, and chronically implanted monkeys, we are defining the timing and localization of cerebral processes which underlie human experience and behavior. Our objectives are: a. To relate the gross indices of neural processes within the brain obtained in human scalp recordings to intracranial recordings of both field and unit activity in primates obtained during the performance of sensorimotor tasks comparable to those studied in man. This work will provide a sounder basis for the physiologic interpretation of human scalp-recorded brain potentials. b. To utilize the methods we have developed for tracing the spatio-temporal patterns of cerebral activity in simple sensorimotor activities to explore the physiologic processes associated with more complex aspects of human experience and behavior. c. To define the course of cortical maturation in the infant and child by tracing the development of specific event-related potentials in relation to the emergence of behavioral competence emphasizing visual and visuomotor processes. This will ultimately form the basis for electrophysiologic analysis of cerebral disorders underlying aberrant neurobehavioral development.